Evolab Guppies

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Exercise 1: Assessing Color Variation Among Males in Guppy Populations

Upper West Stream
Male #| Spot Brightness|
1| 19|
2| 13|
3| 13|
4| 13|
5| 16|
6| 14|
7| 17|
8| 16|
9| 14|
10| 16|
11| 17|
12| 18|
13| 13|
14| 14|
15| 17|
Notes:
* Rivulus species also found in stream
* Female guppies have no spots
* Small amount of Rivulus compared to guppies
* Adequate amount of food for the guppies

Histogram:

Hired Assistant:
Upper West: This is a similar distribution to the one I made. Although it is a smaller sample the distribution is similar.

Upper East: No predators large population.

Meir Creek: Two different predators no guppies, large amount of food.

Lower West: Two different predators large population of guppies small amount of food.

Lower East: Large guppy population one predator adequate guppy food available.

16. Upper West: This stream had a large population of guppies in which the majority of the populations were male. These males all showed a high level of spot brightness. There were few predators in this stream and an adequate amount of food. The water quality is a grey brown on the program.

Upper East: This stream had a higher population of guppies with a varied amount of male and female. There is still a high proportion of bright spotted males however these males are not as bright as in the upper west. There are no predators in this stream and an adequate amount of food. The water quality is a grey brown on the program.

Meir Creek: This area had no guppies present. There is however two different predatory species and a high abundance of guppy food available. The water quality is a grey brown on the program.
Lower West: This stream has a lower proportion of bright males compared to the upper streams. There are also two different predatory species and a smaller amount of guppy food available. The water quality is a dark blue color on the program.

Lower East: This population has a very low spot brightness especially compared to the upper streams. There is one predatory species and an adequate food source. The water quality is a green color on the program.

Exercise 2: Why are Males From Different Locations Different

* Which predators are in the stream along with how many predators there are may affect spot brightness. * Food quality and abundance may affect spot brightness. * Water quality may affect spot brightness.

* Water current may affect spot brightness.
Experiment:
There will be 3 tanks used each with a different water quality. The experiment will be run a total of 4 times in each tank. Each tank will have a control run, a run with the addition of 2 Rivulus, a run with 2 Cichlid A, and a run with 2 Cichlid B. Each tank will begin with 20 guppies, and 10-guppy food to keep constant. Each will run for approximately 360 days. A graph of spot brightness vs proportion of population will be generated for each run. It is hypothesized that the presence of different predators will affect the brightness of guppy spots. If the hypothesis is supported it is predicted that with the presence of rivulus bright spots will be present. With the presence of cichlid A a lower spot brightness will be seen. With the presence of cichlid B an average spot brightness will be seen compared to the other two predators. If the hypothesis and predictions are supported we should see these similar distributions.

Rivulus:

Figure [ 1 ]: Sample distribution with rivulus addition

Figure [ 2 ]: Sample distribution with cichlid A addition

Figure [ 3 ]: Sample distribution with cichlid B addition
Results:
Tank One: Brown Water

Figure [ 4 ]: Tank 1 control after 358 days

Figure [ 5 ]: Tank 1 rivulus addition after 365 days

Figure [ 6 ]: Tank 1 cichlid A addition after 374 days

Figure [ 7 ]: Tank 1 cichlid B addition after 367 days...
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